Rats fed ethanol (30% W/V) and their pair-fed isocaloric dextrose controls will be challenged with IV isoproterenol while under pentobarbitol anesthesia. Blood taken before and 5, 10 and 15' after isoproterenol will be assayed for cAMP using the Gilman competitive binding method. Various organs will similarly be studied for their cAMP response to beta agonists. This will answer the question which organs have altered beta receptors after ethanol feeding. This will suggest which organs are "target" organs for ethanol. Hopefully, it will lead to the explanation why ethanol is especially damaging to the liver, pancreas, skeletal muscle and heart. The brain will similarly be studied after intraventricular injection of agonist. The results will be significant because of the fact that the study will be done in vivo. The results will be compared to reported in vitro results to determine the relevance of the latter. In a second study the calcium (45 Ca) efflux stimulated by norepinephrine will be measured using mitochondria from livers of ethanol and control fed rats. Dose-response curves will be determined to see if ethanol induces subsensitivity of mitochondria to agonists. This study will determine if Ca 2 ion controlled reactions in the liver could be influenced by an ethanol-induced adrenergic subsensitivity. In a third study, liver mitochondria and brain homogenates will be assayed for beta-receptors using affinity chromatography.